Q105 / 180 · COMEDK 2013 · Mathematics
If $\frac{\log x}{a-b}=\frac{\log y}{b-c}=\frac{\log z}{c-a}$, then $x y z$ is equal to
- A$0$
- Correct answerB$1$
- C$-1$
- D$2$
Solution
Let
$\frac{\log x}{a-b}=\frac{\log y}{b-c}=\frac{\log z}{c-a}=k$
$\Rightarrow \quad \log x=k(a-b)$,
$\log y=k(b-c)$
and $\quad \log z=k(c-a)$
Now' $\log x+\log y+\log z=$
$k(a-b+b-c+c-a)$
$\Rightarrow \quad \log (x y z)=0$
$\Rightarrow \quad x y z=1$
Hence, the correct answer is option: 'B'.